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So what: With 90 minutes left in the trading day, 15 million shares have already traded hands. That compares to an average volume of less than 1 million shares. The only news of consequence today was the stock being downgraded to underperform by DA Davidson, as well as analysts at Axiom Securities initiating coverage with a sell rating and a $26 price target.

Now what: Since shares fell off a cliff about an hour after the market opened, there doesn't seem to be any stopping them. If you're a long-term investor then you might want to pull your hair out, but there isn't a solid reason to sell today. The company didn't release any terrible news today, so the market appears to be moving this way based on some analyst recommendations and momentum investors' bets. There may be further downside considering the momentum and new price target, but I wouldn't panic sell unless earnings are terrible when they're released next month.

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